If your device has a blown C1124, don't just swap it. Something killed it:
Transistors often work in pairs (NPN and PNP). c1124 transistor datasheet better
The original C1124 sometimes has a non-isolated tab. Modern replacements (like TIP31C) have a collector-connected tab. If your heatsink is grounded, you must use a mica insulator. If your device has a blown C1124, don't just swap it